Silicon nitride powder of low oxygen content
    1.
    发明授权
    Silicon nitride powder of low oxygen content 失效
    低氧含量的氮化硅粉末

    公开(公告)号:US4983371A

    公开(公告)日:1991-01-08

    申请号:US396328

    申请日:1989-08-21

    IPC分类号: C01B21/068

    CPC分类号: C01B21/068 C01P2006/12

    摘要: Si.sub.3 N.sub.4 powder wherein the total oxygen content of the powder is 0.4% by weight or less is produced by preparing an amorphous Si.sub.3 N.sub.4 intermediate by reacting a Si-containing compound with an N-containing compound and the intermediate is then crystallized wherein "P", multiplication product of(i) the specific surface of the amorphous intermediate (BET in m.sup.2 /g),(ii) the moisture content C.sub.H.sbsb.2.sub.O (in volume ppm) of the atmosphere during handling and(iii) the time t in hours required for handling the amorphous intermediate,is kept smaller than the limit value product P.sub.G of 1000 in accordance with the following equation:"P"=BET (m.sup.2 /g).times.C.sub.H.sbsb.2.sub.O (vol ppm).times.t(h)

    摘要翻译: 通过使含Si的化合物与含N的化合物反应制备无定形的Si 3 N 4中间产物,其中粉末的总氧含量为0.4重量%以下的Si 3 N 4粉末,然后使中间体结晶,其中“P” (i)无定形中间体的比表面积(BET / m2 / g),(ii)处理过程中气氛的水分CH 2 O(体积ppm)的产物和(iii)处理所需的时间t 无规中间体根据下式保持小于1000的极限值乘积PG:“P”= BET(m 2 / g)×CH 2 O(体积ppm)×t(h)

    Silicon nitride powders of low isoelectric point and processes for their
production
    2.
    发明授权
    Silicon nitride powders of low isoelectric point and processes for their production 失效
    低电导点的硅氮化物粉末及其生产工艺

    公开(公告)号:US5066473A

    公开(公告)日:1991-11-19

    申请号:US579236

    申请日:1990-09-04

    IPC分类号: C01B21/068

    CPC分类号: C01B21/0687

    摘要: Silicon nitride powder having a total oxygen content of less than 1.8% by weight and an isoelectric point in 0.001M aqueous KNO.sub.3 solution of below pH 4 is prepared by calcining Si.sub.3 N.sub.4 powder having an oxygen content of 0.4% by weight or less in an oxygen containing atmosphere at temperatures between 700.degree. and 1200.degree. C. for 15 to 90 minutes or by grinding such as Si.sub.3 N.sub.4 powder in water, lower alcohol or a water/alcohol mixture for 15 to 120 minutes.

    摘要翻译: 通过在氧含量为0.4重量%以下氧化氧含量为0.4重量%以下的Si 3 N 4粉末,制备总氧含量小于1.8重量%的含有低于pH 4的0.001M KNO 3水溶液中的等电点的氮化硅粉末 气温在700〜1200℃的温度下浸渍15〜90分钟,或者研磨如Si3N4粉末在水,低级醇或水/醇混合物中15〜120分钟。

    Silicon nitride powders with improved surface properties and processes
for their preparation
    3.
    发明授权
    Silicon nitride powders with improved surface properties and processes for their preparation 失效
    具有改善表面性能的氮化硅粉末及其制备方法

    公开(公告)号:US5030434A

    公开(公告)日:1991-07-09

    申请号:US579237

    申请日:1990-09-04

    IPC分类号: C01B21/068

    摘要: Si.sub.3 N.sub.4 powders having a total oxygen content of less than 1.8% by weight with the proportion of surface oxygen content of more than 65% of the total oxygen content, and having a fluorine content of less than 35 ppm are prepared by annealing Si.sub.3 N.sub.4 powders having a total oxygen content of less than or equal to 0.4% by weight in an oxygen-containing atmosphere at temperatures of 700.degree. C. to 1200.degree. C. for 15 to 90 minutes or by grinding Si.sub.3 N.sub.4 powders having a total oxygen content of less than or equal to 0.4% by weight in water, alcohol or aqueous alcohol 15 to 120 minutes.

    摘要翻译: 总氧含量小于1.8重量%,表面氧含量占总氧含量的65%以上,氟含量小于35ppm的Si 3 N 4粉末是通过退火具有 在含氧气氛中,在700℃至1200℃的温度下,总氧含量小于或等于0.4重量%,持续15至90分钟,或通过研磨总氧含量低于或等于或等于或等于0的Si 3 N 4粉末, 在水,醇或含水醇中等于0.4重量%至15分钟至120分钟。

    Sinterable SI.sub.3 N.sub.4 powders containing sintering additives and a
process for their preparation
    4.
    发明授权
    Sinterable SI.sub.3 N.sub.4 powders containing sintering additives and a process for their preparation 失效
    含烧结添加剂的可烧结SI3N4粉末及其制备方法

    公开(公告)号:US4980322A

    公开(公告)日:1990-12-25

    申请号:US377778

    申请日:1989-07-10

    IPC分类号: C04B35/626 C04B35/584

    CPC分类号: C04B35/584

    摘要: Sinterable Si.sub.3 N.sub.4 powder containing Si.sub.3 N.sub.4 particles and sintering additives wherein Si.sub.3 N.sub.4 particles have an average particle size of less than 1 .mu.m, contain no particle having a diameter greater than 100 .mu.m, have a total content of metallic impurities less than 1000 ppm and an iron content of less than 200 ppm, and wherein the sintering additives are uniformly distributed throughout the powder is prepared by co-grinding pulverulent sintering additive and Si.sub.3 N.sub.4 containing less than 1000 ppm metallic impurities in a spiral jet mill.

    摘要翻译: 含有Si 3 N 4颗粒的可烧结Si 3 N 4粉末和其中Si 3 N 4颗粒的平均粒度小于1μm的烧结助剂,不含直径大于100μm的颗粒,金属杂质的总含量小于1000ppm,铁 含量小于200ppm,并且其中烧结添加剂均匀分布在整个粉末中通过在螺旋喷射磨中共磨粉碎烧结添加剂和含有小于1000ppm金属杂质的Si 3 N 4来制备。

    Process for the preparation of silicon nitride
    7.
    发明授权
    Process for the preparation of silicon nitride 失效
    制备氮化硅的方法

    公开(公告)号:US5075091A

    公开(公告)日:1991-12-24

    申请号:US409275

    申请日:1989-09-19

    IPC分类号: C01B21/068

    CPC分类号: C01B21/0685

    摘要: The process of preparing silicon nitride is improved by reacting silicon-oxygen compounds and a carbon-containing material in an ammonia or ammonia/nitrogen atmosphere at 1300.degree. to 1600.degree. C.

    摘要翻译: 通过使硅 - 氧化合物和含碳材料在氨或氨/氮气氛中在1300°至1600℃下反应来提高氮化硅的制备工艺。

    Process for the production of maleic anhydride
    8.
    发明授权
    Process for the production of maleic anhydride 失效
    马来酸酐生产工艺

    公开(公告)号:US4268448A

    公开(公告)日:1981-05-19

    申请号:US114448

    申请日:1980-01-22

    CPC分类号: C07C51/25 C07C51/252

    摘要: Ethylenically unsaturated C.sub.4 -n-hydrocarbons are oxidized to maleic anhydride by passing a stream of oxygen-containing gas at high temperature over a catalyst of the formulaW.sub.a Mo.sub.b Sb.sub.c Y.sub.d X.sub.e O.sub.xwherein Y=P, Si; X=V, Bi, Te, alkali metal; a and b each=1-12; c=2-20; d=0.2-2; e=0-10; and x is the number of oxygen atoms required to satisfy the remaining valences of the other elements, prepared by reacting an Sb compound and optionally also a V, Bi, Te and/or alkali metal compound, with a solution of a heteropoly acid of Mo and W, drying and tempering the resultant blue complex.

    摘要翻译: 将烯属不饱和C4-n-烃通过使高温含氧气体流在式WaMobSbcYdXeOx的催化剂上氧化成马来酸酐,其中Y = P,Si; X = V,Bi,Te,碱金属; a和b每个= 1-12; c = 2-20; d = 0.2-2; e = 0-10; x是通过使Sb化合物和任选的V,Bi,Te和/或碱金属化合物与Mo的杂多酸的溶液反应而制备的其它元素的剩余价数所需的氧原子数 和W,干燥和回火得到的蓝色络合物。